[ARRL-OK] HAZARDOUS WEATHER OUTLOOK

[arrl-ok@mailman.qth.net]

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
1200 PM CDT FRI MAY 23 2003

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN...WESTERN...
CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS 
OF OKLAHOMA AND WESTERN NORTH TEXAS.

LOCATION...
THE SLIGHT RISK AREA IS WEST OF A LINE FROM PONCA CITY...TO 
SULPHUR...TO MARIETTA. 

TIMING...
THE MOST LIKELY TIME FOR SEVERE THUNDERSTORMS WILL BE LATE TONIGHT.
 
RECOMMENDED ACTIONS...
STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL ACROSS THE 
RISK AREA SHOULD PLAN FOR SEVERE WEATHER OPERATIONS 
TONIGHT...POSSIBLY AS EARLY AS THIS EVENING BUT MORE LIKELY AFTER 
MIDNIGHT. 

DISCUSSION...
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER PARTS OF NORTHERN 
AND EASTERN OKLAHOMA AT MIDDAY ARE EXPECTED TO WEAKEN AND DISSIPATE 
DURING THE AFTERNOON. ASSOCIATED CLOUD COVER ALSO IS EXPECTED TO 
THIN...WHICH WILL ALLOW FOR AFTERNOON HEATING AND DESTABILIZATION. 
DESPITE MODERATELY UNSTABLE CONDITIONS EXPECTED THIS AFTERNOON...THE 
PRESENCE OF A CAPPING LATER OF WARM AIR ALOFT IS EXPECTED TO 
MINIMIZE THE CHANCES OF THUNDERSTORM REDEVELOPMENT OVER THE AREA 
THROUGH EARLY EVENING. 

AN AXIS OF MORE UNSTABLE AIR IS EXPECTED TO EXTEND NORTHWARD FROM 
WEST TEXAS INTO THE HIGH PLAINS OF EASTERN COLORADO AND WESTERN 
KANSAS BY LATE AFTERNOON. THUNDERSTORMS ARE EXPECTED TO DEVELOP IN 
THESE AREAS BY EARLY EVENING...MAINLY IN RESPONSE TO STRONGER 
AFTERNOON HEATING OVER THE HIGHER TERRAIN. THESE THUNDERSTORMS ARE 
EXPECTED TO MERGE INTO ONE OR MORE CONVECTIVE COMPLEXES THIS 
EVENING. NORTHWESTERLY STEERING CURRENTS ALOFT WILL THEN DRIVE THESE 
COMPLEXES SOUTHEASTWARD...MOST LIKELY BRINGING THUNDERSTORMS INTO 
THE FORECAST AREA WELL AFTER DARK. THE NORTHWEST WINDS ALOFT WILL 
PROVIDE SUFFICIENT VERTICAL WIND SHEAR TO ALLOW FOR THE DEVELOPMENT 
OF ORGANIZED COMPLEXES OF POTENTIALLY SEVERE THUNDERSTORMS. LARGE 
HAIL WILL BE THE PRIMARY CONCERN...BUT AS THE NIGHT PROGRESSES THE 
POTENTIAL FOR DAMAGING WINDS MAY INCREASE IF THE THUNDERSTORM 
COMPLEXES CAN BECOME SUFFICIENTLY ORGANIZED. 

AT THIS TIME...WE ARE LOOKING AT TWO POTENTIAL AREAS FOR THE 
DEVELOPMENT OF THUNDERSTORM COMPLEXES THIS EVENING. ONE IS OVER 
NORTHWEST TEXAS...IN OR NEAR THE TEXAS PANHANDLE...WITH THESE 
THUNDERSTORMS POSSIBLY AFFECTING PARTS OF WESTERN NORTH TEXAS AND 
FAR SOUTHWEST OKLAHOMA BY MID TO LATE EVENING AS THEY MOVE 
SOUTHEASTWARD. THE OTHER...AND MORE LIKELY AREA...IS OVER THE 
CENTRAL HIGH PLAINS. THIS COMPLEX WOULD MOVE SOUTHEAST THIS 
EVENING...REACHING NORTHERN OKLAHOMA AROUND MIDNIGHT AND THEN 
ROLLING SOUTHEAST ACROSS THE SLIGHT RISK AREA DURING THE LATE NIGHT 
AND EARLY MORNING HOURS. 

PROBABILITY TABLE...
VALID THROUGH 700 AM CDT SATURDAY MAY 24.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
 � � � � � � �NWS NORMAN COUNTY WARNING AREA...90 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...50 PERCENT.

OTHER HAZARDOUS WEATHER...
ASIDE FROM THE SEVERE WEATHER DANGER...NO OTHER HAZARDOUS WEATHER IS 
EXPECTED THROUGH TONIGHT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY...

THUNDERSTORM OUTLOOK...
A SIMILAR NORTHWEST FLOW WEATHER PATTERN WILL PERSIST THROUGH AT 
LEAST SATURDAY...RESULTING IN A CONTINUED CHANCE OF THUNDERSTORMS 
AND A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE FORECAST 
AREA THROUGH SATURDAY AND SATURDAY NIGHT. OUTFLOW BOUNDARIES FROM 
ANY STORMS TONIGHT COULD PROVIDE A FOCUS FOR SEVERE STORM 
REDEVELOPMENT IN THE AREA ON SATURDAY AFTERNOON. ADDITIONAL 
NIGHTTIME THUNDERSTORM COMPLEXES MAY AFFECT THE AREA SATURDAY 
NIGHT...WITH A CONTINUING POSSIBILITY OF SEVERE WEATHER. 

OTHER HAZARDOUS WEATHER...
HEAVY RAIN AND POSSIBLE FLOODING WILL BE A CONCERN WITH 
THUNDERSTORMS SATURDAY AND SATURDAY NIGHT.